saeamuller



(No Model.)

G. N. SAEG-MULLER. EQUATORIAL MOUNTING.

Patented Man 10, 1891.

qwitmeooeo UNITED STATES PATENT OFFICE.

GEORGE N. SAEGMULLER, OF lVASI-IINGTON, DISTRICT OF COLUMBIA.

EQUATORIAL MOUNTING.

SPECIFICATION forming part of Letters Patent No. 448,081, dated March10, 1891.

' Application filed November 17,1890- Serial No. 371,725. (No model.)

To coll whom it nutty concern.-

Be it known that I, GEORGE N1 SAEGMUL- LER, a citizen of the UnitedStates, residing at lVashington, in the District of Columbia, haveinvented certain new and useful Improvements in Equatorial Mountings;and I do hereby declare the following to be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to make and use the same.

My invention has relation generally to the manner of mounting equatorialinstruments, and particularly to that part which supports the polar axisoutside of the head-stock. light instruments of this kind it has beencustomary to support the instrument at this point by a single wheelhaving a round or are shaped periphery, so as to reduce the bearing-surface to the minimum. Such a device would soon be flattened in avery irregular manner by a large instrument and the efiiciency of thelatter partly, if not wholly, de-

stroyed. A single wheel with a broader bearing-surface would not answeras a substitute for the rounded wheel, for the reason that, while thebearing-face of the collar would be on substantially the same horizontalplane as the top of the wheel, the axis of the collar would be at anangle to the wheel, and consequently that part of the collar having thegreatest diameter would be moving faster than that part having thesmallest diameter, and thereby causing the parts to cramp the bearingand twist the instrument to a greater or less extent out of the positionnecessary for accurate observations. To remove all objections of thiskind is the object. of my invention, and the object is accomplished byproviding a series of thin wheels of the same diameter and mountedloosely upon the same shaft placed parallel with the bearing-face of thecollar which rests on the wheelsas a bearing for said collar.

The invention therefore consists of construct-ions and combinations, allas will hereinafter be set forth in the specification and pointed out inthe claim, reference being had to the accompanying drawing, in which thefigure represents an elevation, partly in section, of a head-stock, itssupporting-base, and

steel and'secured to or formed integral with the polar axis, and Afriction wheels or rollers arranged in a frame a which is forced upwardby any desired means, such as a spring or screw, the latter being shownin the present instance and marked or. The collar a is so beveled thatthat portion which contacts with the wheels or rollers A will be on ahorizontal plane, that relation being retained no matter atwhatinclination the polar axis maybe set because of the particularlatitude in which the instrument is to be set up or placed. 7

The wheels or rollers A are of the same diameter and loose upon the sameaxle a so that each will be free to revolve independ ently of eachother, so that when in contact with the beveled face a of the collareach wheel will be free to revolve in accordance with the movement ofthat part of the beveled face it is in contact with and irrespective ofthe movement of its adjoining wheel or wheels, which may be two or more.

lVhat I claim as new is In an equatorial instrument, the combination ofthe polar axis having a collar with horizontal bearingface anda seriesof wheels or rollers mounted upon a single shaft and supporting thepolar axis by contacting with the beveled face of said collar.

In testimony whereof I affix my signature in presence of two witnesses.

GEORGE N. SAEGMULLER. \Vitnesses:

GEO. R. BYINGTON, M. F. IIALLEOIL.

